Air and space craft with enhanced lift

ABSTRACT

An aircraft includes a fuselage having an upper surface and a lower surface that define an airfoil shape in cross-section along a vertical plane such that horizontal movement of the fuselage through air produces a lift force in a vertical direction. The aircraft also includes a plurality of modules attached to the fuselage. Each module includes an upper jet engine directed above the upper surface of the fuselage and an opposed lower jet engine directed below the lower surface of the fuselage.

PRIORITY CLAIM

This application is a Continuation-in-Part of U.S. patent applicationSer. No. 15/637,922, filed on Jun. 29, 2017, published as US2018/0222603on Aug. 9, 2018 and issued as U.S. Pat. No. 10,633,120 on Apr. 28, 2020,which claims priority to U.S. Provisional Patent Application No.62/499,759, filed on Feb. 6, 2017; U.S. Provisional Patent ApplicationNo. 62/601,356, filed on Mar. 20, 2017; U.S. Provisional PatentApplication No. 62/601,821, filed on Apr. 3, 2017; and U.S. ProvisionalPatent Application No. 62/602,808, filed on May 8, 2017, each of whichis incorporated by reference herein. This application claims the benefitof U.S. Provisional Patent Application No. 62/922,540, filed on Aug. 15,2019, which is incorporated by reference herein.

BACKGROUND

The present disclosure relates to technology for air and space travel.

Various kinds of aircraft are known including fixed-wing airplanes,lighter-than-air craft, helicopters. In many forms of aircraft,propulsion is provided by one or more jet engines or by a rotatingpropeller, or propellers, powered by internal combustion engines. Spacecraft are generally distinct from aircraft and require differentpropulsion systems, such as rockets, because jet engines and internalcombustion engines generally require air to operate.

SUMMARY

An example of an aircraft includes a fuselage having an upper surfaceand a lower surface that define an airfoil shape in cross-section alonga vertical plane such that horizontal movement of the fuselage throughair produces a lift force in a vertical direction. A variety of aircrafthaving an oblate spheroid as the leading central portion of its compoundcomposition and having an adjacent lift profile assembly (LPA) trailingportion, that completes a 3 D lift geometry that generates lift over thecraft's entire upper surface when propelled through air. The embodimenthaving this gliding lift geometry is referred to herein as (LEOS) LiftEnhanced Oblate Spheroid or (LEOS w PA) w/Perimeter Appendage/s, such aswings tails etc.

An aircraft may include a plurality of modules (e.g. modules that eachinclude a pair of engines attached to the fuselage), each moduleincluding an upper jet engine directed above the upper surface of thefuselage and an opposed lower jet engine directed below the lowersurface of the fuselage. Each opposed engine of such a pair may be maderotatable and housed in a corresponding module or may have a fixedlocation and orientation with respect to the fuselage.

The fuselage may be circularly symmetric about a central axis. Eachmodule may be separately rotatable about a vertical axis that extendsparallel to the central axis. The fuselage may include an oblatespheroid portion that is symmetric about a central axis and furtherinclude a lift profile assembly extending laterally from a section ofthe oblate spheroid portion along a plane that is perpendicular to thecentral axis, the combination of the oblate spheroid portion and thelift profile assembly forming the airfoil shape. The lift profileassembly may be rotatable about the central axis. The lift profileassembly may be at least partially separable from the oblate spheroidportion from a lift-generating configuration to a high-dragconfiguration. The fuselage may include a frame formed by frame membersextending radially from the central axis with optional perpendicularcross members. The fuselage may be formed of prefabricated wedge-shapedsections that are joined along the central axis. Upper jet engines andlower jet engines of the plurality of modules may be configured togenerate a combined thrust vector and a central controller may beconfigured to control thrust generated by individual ones of the upperjet engines and lower jet engines to change the combined thrust vectorand thereby change orientation of the aircraft. The upper jet enginesand lower jet engines may be fixed with respect to the fuselage and thecentral controller may be configured to change direction and magnitudeof the combined thrust vector by changing magnitudes of thrust generatedby individual ones of the upper jet engines and lower jet engines. Theaircraft of may include a first air-tight door and a first air-lockflange in the upper surface of the fuselage and a second air-tight doora second air-lock flange in the lower surface of the fuselage.

An example of an aircraft includes a fuselage having an oval shape incross-section along a horizontal plane and having an airfoil shape incross-section along a vertical plane perpendicular to a primary axis ofthe oval shape and a plurality of pairs of jet engines, each pair of jetengines including an upper jet engine mounted above an upper surface ofthe aircraft and a lower jet engine mounted below a lower surface of theaircraft, the upper jet engine and the lower jet engine controlled by acentral controller.

The fuselage may include an oblate spheroid portion that is symmetricabout a central axis and further include a lift profile assemblyextending laterally from a section of the oblate spheroid portion alongthe horizontal plane. The lift profile assembly may be rotatable aboutthe central axis. The lift profile assembly may be at least partiallyseparable from the oblate spheroid portion from a lift-generatingconfiguration to a high-drag configuration. The fuselage may include aframe formed by frame members extending radially from the central axis.Upper jet engines and lower jet engines of the plurality of modules maybe configured to generate a combined thrust vector and a centralcontroller may be configured to control thrust generated by individualones of the upper jet engines and lower jet engines to change thecombined thrust vector to thereby change a flightpath of the aircraft.

An example of a method of operating an aircraft includes generating liftby a fuselage having an upper surface and a lower surface that define anairfoil shape in cross-section along a vertical plane such thathorizontal movement of the fuselage through air produced by the thrustgenerates a lift force in a vertical direction; generating thrust by aplurality of modules attached to the fuselage, each module including anupper jet engine directed above the upper surface of the fuselage and anopposed lower jet engine directed below the lower surface of thefuselage; and controlling a flightpath of the aircraft by a centralcontroller changing thrust of the upper jet engine and the lower jetengine of each of the plurality of modules to thereby change a combinedthrust vector of the plurality of modules.

An example of an aircraft includes: a fuselage having an upper surfaceand a lower surface; and a plurality of planetary modules housed in thefuselage, an individual planetary module having a first jet enginedirected outward of the upper surface of the fuselage and a second jetengine directed outward of the lower surface of the fuselage, theindividual planetary module rotatable within the fuselage about avertical axis. In each pair, each upper engine's thrust discharge may beopposed and in a plane parallel and above the upper surface of theaircraft and each lower engine's thrust discharge may be opposed and ina plane parallel and below the lower surface of the aircraft,irrespective of flight path vector orientation. Thus, the engine'scollective or aggregate thrust is always in line and opposite thecraft's trajectory. The useful work resulting from each pair of opposedengines is a highly enhanced efficiency, performance, and control.

The individual planetary module may include an interior volume thatmaintains an internal pressure that is a higher pressure than an ambientpressure, the first and second jet engines extending through the sealedinterior volume, the first and second jet engines generating thrustwithin the individual planetary module. The aircraft may include a firstrocket engine and a second rocket engine in the individual planetarymodule. The aircraft may include a first engine swapping mechanismconfigured to swap the first jet engine and the first rocket engine suchthat the first rocket engine is directed outward of the upper surface ofthe fuselage; and a second engine swapping mechanism configured to swapthe second jet engine and the second rocket engine such that the secondrocket engine is directed outward of the upper surface of the fuselage.The engine swapping mechanism may comprise an axis of rotation, thefirst rocket engine and the first jet engine being rotatable about theaxis of rotation between an active position and an inactive position.The individual planetary module may be mounted within the fuselage bymeans of a rotational support and placement system that includes anelectrodynamic suspension system. The fuselage may be circular incross-section along a horizontal plane and a habitable space, such as apassenger cabin may extend around a central area in a ringconfiguration. In other examples, habitable space, including passengercabins may be located in the central area. The aircraft may include anautomated delivery system extending in the passenger cabin to deliveritems from a central location to passengers seated or prone in thepassenger cabin. The upper surface and the lower surface of the fuselagemay define an airfoil shape in cross-section along a vertical plane suchthat horizontal movement of the fuselage through air produces a liftforce in a vertical direction. The fuselage may be substantiallycircularly symmetric about a central axis such that horizontal movementof the fuselage in any horizontal direction produces a lift force in thevertical direction. The aircraft may include a gyroscopic system that iscircularly symmetric about the central axis. The aircraft may alsoinclude one or more booster rockets physically attached to the fuselageby detachable couplings.

An example of a method of operating a heavier-than-air craft that issubstantially symmetric about a central axis includes orienting theheavier-than-air craft to align a first portion of the heavier-than-aircraft with a direction of travel; and subsequently rotating theheavier-than-air craft relative to the direction of travel to align asecond portion of the heavier-than-air craft with the direction oftravel, the second portion having a substantially similar profile to thefirst portion.

The method may further include rotating the heavier-than-air craft bygenerating thrust using a plurality thrust generators that may berotatable through 360 degrees about axes that are parallel, orsubstantially parallel to the central axis. The method may include oneor more of the plurality of thrust generators generating thrust directedin a direction opposite to the direction of travel. The method mayinclude all of the plurality of thrust generators generating thrustdirected in directions other than the direction of travel to change thedirection of travel without changing the orientation of the centralaxis. The method may include, when the first portion is aligned with thedirection of travel the first portion increases in temperature androtating the heavier-than-air craft relative to the direction of travelis triggered by a temperature measured in the first portion exceeding athreshold temperature.

An example of a rotatable planetary module for providing thrust includesan upper cover; a lower cover; a first jet engine having an air intakeextending through the upper or lower cover and an exhaust nozzleextending through the upper or lower cover; a second jet engine havingan air intake extending through the upper or lower cover and an exhaustnozzle extending through the upper or lower cover; an axis of rotationthat extends along a first direction through the upper cover and thelower cover; and a coupling that extends about the planetary module withcircular symmetry about the axis of rotation, the coupling providingphysical support for the planetary module and providing rotationalfreedom about the axis of rotation. The coupling may be anelectrodynamic suspension system. One or more dampers may be used toselectively close and/or bypass intake or exhaust openings as needed.

An example of an aircraft includes a fuselage having an upper surfaceand a lower surface; and a plurality of planetary modules housed in thefuselage, an individual planetary module having a first rocket directedoutward of the upper surface of the fuselage and a second rocketdirected outward of the lower surface of the fuselage, the individualplanetary module rotatable within the fuselage about a vertical axis.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-B illustrate an aircraft with circular symmetry and rotatableplanetary modules.

FIGS. 2A-B shows another example of an aircraft with circular symmetryand rotatable planetary modules.

FIGS. 3A-G illustrate examples of using rotatable planetary modules inan aircraft.

FIGS. 4A-B show rotatable planetary modules in an aircraft.

FIG. 5 shows an example of a planetary module with two jet engines incross section.

FIG. 6 shows another example of a planetary module with two jet enginesin cross section.

FIGS. 7A-G show examples of planetary modules with jet and rocketengines.

FIG. 8 an example of a planetary module with two jet engines sharing anintake manifold.

FIGS. 9A-E show an example of a planetary module with engine swappingmechanism.

FIGS. 10A-B show an example of a non-circular aircraft with fourplanetary modules.

FIG. 11 shows an example of an aircraft with a passenger cabin.

FIG. 12 shows an example of an aircraft with a passenger cabin in crosssection.

FIG. 13 shows an example of an aircraft with access to planetarymodules.

FIG. 14 shows an example of an aircraft with booster rockets.

FIG. 15 shows an example of an aircraft with three planetary modules.

FIG. 16 shows an example of an aircraft with four planetary modules.

FIG. 17 shows an example of an aircraft with a Lift Profile Assembly(LPA) in expanded view.

FIG. 18 shows an example of an aircraft with LPA in place.

FIG. 19 shows an example of a cross sectional view of an aircraft withLPA.

FIG. 20 illustrates an example of an LPA.

FIGS. 21A-G illustrate examples of aircraft fuselage shapes.

FIGS. 22A-C illustrate examples of an aircraft with jet enginescontrolled by a central controller.

FIGS. 23A-E illustrate examples of an LPA that is separable forhigh-drag.

FIGS. 24A-D illustrate examples of aircraft with a central axis.

FIGS. 25A-C illustrate an example of aircraft with air-tight doors andair-lock flanges.

FIG. 26 illustrates another example of aircraft with air-tight doors andair-lock flanges.

DETAILED DESCRIPTION

Certain embodiments of the present technology described herein relate toair and space craft that provide a high degree of maneuverability bygenerating thrust in planetary modules that are rotatable to allowthrust direction to be modified. Thrust may be generated by jet enginesand/or rocket engines located in such planetary modules and thus may beused in air and/or space.

In an embodiment, a combined aircraft/spacecraft is symmetric about acentral vertical axis so that it has a disk shape (i.e. shaped like “aflying saucer”). The fuselage of such an aircraft may be shaped so thatlift is generated as the craft moves laterally through air. (Because itflies through air, it may be referred to as an “aircraft” althoughunlike conventional aircraft it may not be limited to air travel and mayalso operate as a spacecraft. The term “aircraft” is used herein torefer to a craft capable of, but not limited to, flying through air.)Optional wings are not required in such an aircraft because the fuselagehas an airfoil shape (i.e. an airfoil shape in cross section).Propulsion may be provided by jet engines in planetary modules thatgenerate thrust when flying in the atmosphere. This allows thrustgenerated by jet engines to be directed in various directions as desiredto control acceleration, deceleration, direction of travel, andorientation when in air.

In an embodiment, propulsion may alternatively be provided by rocketengines in planetary modules that generate thrust when flying in space(e.g. above approximately 70,000 feet). This allows thrust generated byrocket engines to be directed in various directions as desired tocontrol acceleration, deceleration, direction of travel, and orientationwhen in space. Rocket engines may be located in the same planetarymodules as jet engines or may be located in separate planetary modules.

FIG. 1A shows an example of an aircraft 100. Aircraft 100 is diskshaped, with an upper surface, and lower surface (not visible in FIG.1A) that meet along a circular perimeter. Unlike a conventional aircraftthat has wings and a fuselage, aircraft 100 has a fuselage that iswing-shaped in cross-section so that lift is produced when aircraft 100moves horizontally through the air. Aircraft 100 is symmetric about acentral axis so that travel in any horizontal direction (a directionperpendicular to the central axis) produces lift. The lift forcegenerated is independent of the orientation of aircraft 100 about thecentral axis. Thus, aircraft can fly equally well forwards, backwards,or sideways. It will be understood that the terms “forwards,”“backwards” and “sideways” are generally used with respect to anaircraft or other object that has a clearly defined nose, tail, andsides, whereas aircraft 100 is circularly symmetric and does not havesuch easily identified features, and it will be understood that adesignated portion of aircraft 100 may be considered the front, while anopposing portion may be considered the back, and portions laterallydisposed on either side may be considered “sides” for purposes ofdiscussing orientation, although such designations may be arbitrary forsome aircraft that do not have a preferred orientation when flying.

Conventional aircraft have engines (e.g. jet or turboprop engines)mounted to generate thrust along the direction of travel, whichgenerally means that such engines are permanently mounted to generatethrust substantially parallel to an aircraft fuselage. Wings areconfigured so that they generate lift when the aircraft moves along thisdirection of travel. Changes in the direction of travel require changingthe orientation of such an aircraft, i.e. such aircraft travelnose-first, and the nose of the aircraft must be turned to the newdirection of travel. Such a change in direction may require banking andturning through a relatively wide radius to reach the new orientation.Changing direction is generally accomplished using a rudder and/orailerons rather than by changing the direction of thrust.

In contrast with conventional aircraft, aircraft 100 includes planetarymodules 102 a-d within the fuselage, mounted so that they are rotatablewithin the fuselage and can direct thrust in different directions. Eachplanetary module is rotatable within the fuselage about a vertical axis(i.e. an axis that is parallel to, or substantially parallel to thecentral axis of the aircraft). Planetary modules may be rotatablethrough 360 degrees, or some angular range that is less than 360degrees, e.g. through 270 degrees, 180 degrees or some other range.While aircraft 100 has four planetary modules 102 a-d, it will beunderstood that the number of modules may vary and that the four modulesshown are by way of example. Planetary modules that generate thrust maybe provided in various ways and may have a variety of configurationsdepending on the application. Various examples of planetary modules areprovided below.

In addition to planetary modules 102 a-d, aircraft 100 has fins 104 a-dthat are rotatably mounted on the upper surface 116 of aircraft 100.Fins may be rotatable through 360 degrees, or some angular range that isless than 360 degrees. Fins 104 a-d may be used to maneuver aircraft 100in flight. Fins 104 a-d may be used with planetary modules 102 a-d tocontrol the direction of travel of aircraft 100. Fins 104 a-d mayprovide directional control in case of loss of power when planetarymodules 102 a-d may not generate thrust. In some examples, one or morefins may be fixed e.g. two of four fins may be fixed while two arerotatable, or all four may be fixed. The number of fins may vary. Insome examples, no fins may be provided, while in other cases one or morefins (e.g. four fins) may be provided. Fins may also be provided along alower surface of an aircraft. Fins may protrude a fixed distance from asurface of aircraft 100, or may be retractable, or partiallyretractable. For example, fins may be used for maneuvering in air andmay be retracted when flying through space. Some fins may retract, orpartially retract, while others remain fixed. The fin feature may beincorporated with planetary modules 102 a-d as an addition above intakeand discharge manifolds.

FIG. 1B shows aircraft 100 in cross section along a diameter thatintersects central axis 110. FIG. 1B illustrates the airfoil shape ofaircraft 100 that generates lift. It can be seen that lower surface 114is flatter than upper surface 116 so that upper surface 116 forms a“suction surface” while lower surface 114 forms a “pressure surface”when aircraft 100 moves laterally through air, i.e. moves in a directionperpendicular to central axis 110. A variety of different profiles maybe used to generate an appropriate lift force according to requirements.For example, high speed aircraft may have a lower profile and may createless lift at a given speed, while slower aircraft (e.g. cargo aircraft)may have a higher profile and create more lift at a given speed toenable them to fly with relatively heavy cargo. The profile of anaircraft 100 may be configured according to its design weight and speedrange so that when it operates in its designed speed range, the liftgenerated is greater than its design weight.

FIG. 2A shows an example of an aircraft 200 that includes multipleplanetary modules. In this case, there are two kinds of planetarymodules. First planetary modules 220 a-d contain jet engines to providethrust when in air. In this example, each first planetary moduleincludes two jet engines, a first jet engine directed outward of theupper surface of the fuselage and a second jet engine directed outwardof the lower surface of the fuselage (not visible in FIG. 2A). Both jetengines of a planetary module may be substantially aligned in theirlateral orientation, i.e. if a planetary module is oriented to directthrust in a northerly direction, then both jet engines of the module aredirected towards the south to generate thrust towards the north. Insteadof jet engines being arranged in a parallel configuration, jet enginesmay be arranged in an X configuration so that the first jet engine hasan air intake on the lower surface (not shown) and an exhaust on theupper surface, while the second jet engine has an air intake on theupper surface and an exhaust on the lower surface (not shown). Jetengines may have their intake and exhaust manifolds covered by coversthat are flush with the surface of the aircraft as shown in FIG. 2A,which shows pressurized covers over jet engines of planetary modules 220a-d.

Second planetary modules 222 a-d contain rocket engines to providethrust when in space. Rocket engines may be mounted in planetary modulessimilarly to jet engines. A first rocket engine directed outward of theupper surface of the fuselage and a second rocket engine directedoutward of the lower surface of the fuselage. Both rocket engines of aplanetary module may be substantially aligned in their lateralorientation, i.e. if a planetary module is oriented to direct thrust ina northerly direction, then both rocket engines of the module arepointed towards the south so that their thrust is directed towards thenorth. Rocket engines are arranged in an X configuration so that thefirst rocket engine has an exhaust on the upper surface, while thesecond rocket engine has an exhaust on the lower surface. In addition,while no fins are shown in FIG. 2A, fins may be provided on aircraftsurfaces in this and other embodiments. Also, not visible in FIG. 2A areretractable spoilers around the edge of aircraft 200, which may be usedto provide increased drag for slowing down or turning aircraft 200. FIG.2B illustrates a spoiler 224 in an extended position where it producesincreased drag in air (spoilers may remain retracted in space). Anysuitable number of spoilers may be positioned around the outer edge ofaircraft 200 and may be centrally controlled to produce drag asrequired.

FIG. 3A-F illustrate how planetary modules, including planetary moduleshaving rocket and/or jet engines, may be oriented differently in flight.FIG. 3A shows planetary modules 1-4 of aircraft 300 in top-down viewincluding exhaust (indicated by arrows coming from each respectiveplanetary module 1-4. The direction of travel is indicated by the arrow(up the page in this view). In general, the direction in which exhaustis expelled is opposite to the direction in which thrust is generated sothat thrust is generally along the direction of travel in FIG. 3A.Planetary modules 3 and 4 are shown with their thrust directed outwardsfrom the centerline of aircraft 300 in a balanced arrangement to createnet thrust along the direction of travel. This configuration may be usedto maintain stability for example when taking off or landing when thereis insufficient speed for fins and/or spoilers to maintain stability.Planetary modules 3 and 4 may provide side forces to stabilize aircraftat low speed.

FIG. 3B shows a simplified top-down view that is similar to FIG. 3A. Inthis case, arrows indicate the direction in which exhaust is expelled(opposite to the direction of thrust). Thus, in FIG. 3B all planetarymodules are aligned along the direction of travel (up the page) togenerate thrust in the direction of travel, with exhaust being expelledin the opposite direction. This may be considered a linear travel modeof operation in which all planetary modules 1-4 are aligned along thedirection of travel to keep aircraft 300 travelling in the samedirection.

FIG. 3C shows an example of how planetary modules may be used to directthrust in different directions and thereby rotate the aircraft 300. FIG.3C is a top-down view. As can be seen, planetary modules 1-4 areoriented in a circumferential arrangement so that their thrust generatesa turning force and causes aircraft to rotate counter-clockwise asshown.

FIG. 3D shows an example in which the orientations of planetary modules1-4 are opposite of that shown in FIG. 3C so that they generate aturning force in the opposite direction. The result is clockwiserotation of the aircraft as shown. No direction of travel is indicatedin FIGS. 3C-D. Rotation may occur independently of the direction oftravel, and may occur without travel, i.e. when an aircraft is notmoving laterally. It will be understood that rotation may be combinedwith lateral movement so that an aircraft may rotate as it is flying.This may be achieved with relatively small changes to thrust directions,e.g. by offsetting planetary modules 1-4 a few (<10) degrees from thedirection of travel and/or by modifying power generated by differentplanetary modules (decreasing power on one side while increasing poweron an opposing side for example). As an aircraft rotates to a neworientation, planetary modules may realign accordingly so that theirthrust is directed as appropriate (e.g. directed along the direction oftravel to accelerate, or directed opposite the direction of travel todecelerate). Such rotation may be achieved while flying level to theground, i.e. while maintaining the orientation of the central axissubstantially vertical with respect to the ground, so that no banking isneeded.

FIG. 3E shows an example in which all planetary modules 1-4 are alignedto generate thrust in a direction that is opposite to the direction oftravel. The direction of travel is up the page in FIG. 3E and allplanetary modules direct thrust up the page. This may be used to providedeceleration. For example, when preparing to land, an aircraft mayreduce speed by reversing thrust of one or more planetary modules. Also,when an aircraft that is configured for space travel reenters theatmosphere, reverse thrust may decelerate the aircraft to keep itsreentry speed at a safe level and to control reentry trajectory.

FIG. 3F illustrates an example in which the direction of thrust of allplanetary modules 1-4 is perpendicular to the direction of travel(indicated by the large arrow). This configuration allows for a rapidchange in direction without the need for banking or otherwise changingthe orientation of the aircraft (e.g. lateral travel direction maychange while central axis remains vertical). An aircraft may change fromtravelling North to travelling West without changing its orientation.Thus, in this example all of the thrust generators are generating thrustdirected in directions other than the direction of travel to change thedirection of travel. This is done without banking, i.e. without changingthe orientation of the central axis (which is perpendicular to thetop-down view shown). It will be understood that in addition tomodifying the direction of thrust, the amount of thrust generated byeach planetary module may be controlled to create a turning force (e.g.increasing thrust on one side and/or reducing on an opposing side).

FIG. 3G illustrates how rotating an aircraft to change its orientationwhile under way may provide significant benefits. Specifically, FIG. 3Gshows a method of operating an aircraft that has circular symmetry(substantially symmetric about a central axis) and has a thrustgenerator, or thrust generators, that can change their direction ofthrust to rotate the aircraft, e.g. rotatable planetary modules. Thismethod may be used during reentry into the earth's atmosphere by anaircraft that is configured for air and space travel. During reentry,the temperature is measured 350 at a leading location of the aircraft.Multiple temperature transducers may be located on or near the surfacesof the aircraft, particularly along portions of the aircraft that tendto become hot during reentry. Generally, heat generated by frictionduring reentry is concentrated at the leading portion of a spacecraft.Temperature transducers may be located along, or close to, the edge of acircularly symmetric aircraft (i.e. close to where the upper surface andlower surface meet). Some location along the edge may be considered aleading location at any given time (i.e. some portion of the aircraft isa lead portion at a given time). The temperature of the leading locationis measured and is compared with a threshold temperature to determine ifthe temperature of the leading location is greater than the thresholdtemperature 352. If the temperature at the leading location is notgreater than the threshold temperature, then the aircraft may maintainthe current orientation 354. If the temperature at the leading locationis greater than the threshold then the aircraft may be rotated 356 (e.g.using planetary modules to offset thrust from the direction of travel)thereby rotating the leading location. The former lead portion can thencool down while a new portion is rotated to the front to become the leadlocation. In this way, heat generated by friction during reentry may bedistributed among various portions of the aircraft instead ofconcentrating the heat in a particular portion (e.g. a nose section).When a given portion becomes hot, it is rotated out of the lead positionso that heat can dissipate. Since both portions have substantially thesame profile there is little or no change in drag or friction from sucha change in orientation. In some cases, rotation may be continuous, andan aircraft may rotate with an angular velocity that is controlled toensure that heat is distributed adequately and no portion exceeds athreshold temperature.

Planetary modules may be mounted within a fuselage in various ways. FIG.4A shows an example of an aircraft 400 in which planetary modules 440a-d are rotatably mounted using an electrodynamic suspension system.Electrodynamic suspension is a form of magnetic levitation in whichconductors are exposed to time-varying magnetic fields. This induceseddy currents in the conductors that create a repulsive magnetic field.The repulsive magnetic field holds the two objects apart or, at least,reduces contact. Time varying magnetic fields can be caused by relativemotion between two objects such as between an electrodynamic ring arounda planetary module and a corresponding electrodynamic ring in aplanetary module receptacle in an aircraft. Magnetic fields may becontrolled to maintain a fixed distance between an outer surface of aplanetary module and an inner surface of the aircraft (e.g. usingelectromagnets arranged around an opening in the aircraft that encirclesthe planetary module).

Planetary modules 440 a-d may lock into position and electrodynamicsuspension may be switched off when they are expected to maintain thesame orientation for an extended period. When planetary modules are tobe rotated, the electrodynamic suspension may be activated so thatplanetary modules may be easily be rotated within the aircraft. In somecases, stepper motors, servo motors, or other electrical motors are usedto mechanically turn planetary modules within an aircraft.

FIG. 4A shows a cut-away view of planetary modules 440 a-d in theiroperating position within aircraft 400. It can be seen that planetarymodules 440 a-d are substantially flush with surfaces of aircraft 400 sothat aircraft 400 is aerodynamic. A planetary module has an upper coverthat is substantially flush with the upper surface of the aircraft and alower cover that is substantially flush with the lower surface of theaircraft. Openings for intake and/or exhaust may be designed to beaerodynamic and may include retractable covers to reduce drag when notin use e.g. rocket exhaust may be covered when rocket is not in use andthe intake and/or exhaust of a jet engine may be covered when the jet isnot in use. In some cases, a scoop may project outward of a surface ofan aircraft to facilitate air intake for a jet engine. Such a scoop maybe retractable to reduce drag when the jet engine is not in use. In somecases, a retractable scoop may cover the air intake when it is in theretracted position. In some cases, a nozzle may project outward of asurface of an aircraft to direct the exhaust of a jet or rocket. Such anozzle may be retractable to cover the exhaust when not in use.

FIG. 4B shows an exploded view of some components of aircraft 400.Planetary modules 440 a-d are shown separately from respectivereceptacles 442 a-d in aircraft 400. An individual planetary module 440a is designed to fit in corresponding receptacle 442 a so that an uppercover of planetary module 440 a is flush with an upper surface ofaircraft 400 and a lower cover of planetary module 440 a is flush with alower surface of aircraft 400 (some elements may extend beyond thesurfaces such as fins, nozzles, cowlings, or other projectingcomponents). Rings of electromagnetic elements extend about planetarymodules and receptacles as components of the electromagnetic suspensionsystem that allows planetary modules to be rotated. For example,planetary module 440 a has rings 444 of magnetic elements (two rings inthis example) that are coupled with rings of correspondingelectromagnetic elements around an inner surface of receptacle 442 a.Rings of electromagnetic elements around inner surface of receptacle 442a may be controlled to position planetary module 440 a and to rotate itas desired.

FIG. 5 illustrates an example of a planetary module 500 in crosssection, showing two jet engines 502, 504 arranged in an Xconfiguration. A first jet engine 502 extends from bottom right to topleft, having an air intake 505 extending through a lower surface 506 andhaving an exhaust nozzle 508 extending through an upper surface 510.Thus, first jet engine 502 is directed outward of upper surface 510 andtoward the left side of FIG. 5 to generate thrust to the right side. Asecond jet engine 504 extends from the top right to the bottom left,having an air intake 512 extending through upper surface 510 and havingan exhaust nozzle 514 extending through the lower surface 506. Thus, thesecond jet engine is directed outward of the lower surface and towardthe left side of FIG. 5 to generate thrust to the right side. First andsecond jet engines 502, 504 may be offset from a central axis of theplanetary module 500 so that they do not intersect. FIG. 5 also shows afuel tank 518 located within planetary module 500. In some cases, a fueltank within a planetary module may provide fuel to jet engines when aplanetary module is unable to obtain fuel from a main fuel source thatis external to the planetary module. Such a local source of fuel mayhave advantages at times, for example, when pumping fuel from otherareas of the aircraft may be difficult or impossible (e.g. in emergencysituations, loss of power, during high-speed maneuvers when g-forces arehigh).

FIG. 6 shows another example of a planetary module including two jetengines in an X configuration with air intakes and exhaust nozzlesretracted. In this configuration, air intake 512 is retracted so that itis flush with upper surface 510 and exhaust nozzle 508 is also retractedand is flush with upper surface 510. Similarly, air intake 505 andexhaust nozzle 514 are retracted and are flush with lower surface 506.This configuration may seal jet engines when in space and may provideless drag when in air and the jet engines are not in operation.

FIG. 7A shows another example of a planetary module 700 including twojet engines 702, 704. In this example, jet engines 702, 704 areconfigured with separate air intake ducts 706, 708 that substantiallyredirect air provided to the jets so that jets may be oriented in anear-horizontal configuration and thus generate thrust that has a largelateral component. Jet engine 702 is coupled to air intake duct 706 andjet engine 704 is coupled to air intake duct 708. In other examplesexhaust ducts may redirect exhaust gasses. For example, exhaust gas froman upper jet may be redirected from its initial direction (along theaxis of rotation of the jet turbines) to a more vertical direction sothat exhaust gas is directed downwards in a near-vertical direction.This may produce thrust that has a larger vertical component than if theexhaust was not redirected. Vertical thrust provided by thisconfiguration may be useful during takeoff and landing when liftprovided by lateral movement is not sufficient. In some cases,redirecting may be configurable as needed using a movable duct or nozzleso that thrust may be directed vertically for takeoff and landing andmay be more lateral during flight. Both air intake and exhaust ducts mayredirect air and exhaust gas respectively so that redirecting may beperformed at the intake side, the exhaust side, or both intake andexhaust sides.

While planetary module 700 of FIG. 7A has two jet engines that aremounted in similar configurations, oriented in mirror-imageorientations, in other examples, two jet engines in a planetary modulemay have different configurations.

In addition to jet engines 702, 704, planetary module 700 includesrocket engines 712, 714, which are paired with corresponding jet engines702, 704. Rocket engine 712 is paired with jet engine 702, having aparallel orientation. Rocket engine 714 is paired with jet engine 704,having a parallel orientation. In some examples, a planetary module mayswitch between jet engines and rocket engines according to conditionswhile maintaining thrust in the same direction. For example, rocketengines may be used in space while jet engines are used in air.

FIG. 7B shows another example of a planetary module 750 that includesboth jet engines 752, 754, and also rocket engines 762, 764. Jet engine752 is paired with rocket engine 762 so that they are parallel and haveexhaust outlets close together on the top of planetary module 750. Jetengine 754 and rocket engine 764 are paired so that they are paralleland have exhaust outlets close together on the bottom of planetarymodule 750. In this example, jet engines 752, 754 are arranged in an Xconfiguration as are rocket engines 762, 764.

Some planetary modules may be configured with jet engines, while otherplanetary modules are configured with rockets. A single module may alsobe configured with both jet engines and rocket engines as previouslyshown. Jet engines and rocket engines may be mounted so that theirpositions within a planetary module are fixed (i.e. they rotate as partsof the planetary module but retain their respective positions within theplanetary module). Alternatively, jet engines and rocket engines may bemounted so that they can move within a planetary module thereby allowingreconfiguration of the planetary module. For example, a jet engine maybe paired with a rocket engine so that they can be swapped as required.When flying through air, the jet engine may be in an active position andthe rocket engine may be in an inactive position. When flying throughspace, the rocket engine may be in the active position and the jetengine may be in the inactive position. A suitable engine swappingmechanism may be configured to swap engines as needed so that theappropriate engine is active at any time.

FIG. 7C shows a cross section of another planetary module 760 thatincludes rocket and jet engines with engine swapping mechanisms. In thisexample, an upper engine swapping mechanism 762 a is configured to moveupper jet engine 764 a and upper rocket engine 766 a, while a lowerengine swapping mechanism 762 b is configured to move lower jet engine764 b and lower rocket engine 766 b. Engines are shown in retractedpositions where they are inactive. An engine cover-rudder 780 isprovided along the upper surface of planetary module 770 where an engineis located in the active position. Upper jet engine 764 a is mountedwith a seal 782 that seals against an opposing seal 784 when upper jetengine 764 a is in the active position so that the interior of planetarymodule 760 may be pressurized. Upper rocket engine 766 a is mounted witha seal 786 that similarly seals against opposing seal 784 when upperrocket engine 766 a is in the active position. An air intake gate seal788 is provided to seal the air intake in engine cover-rudder 780 asneeded (e.g. when there is no engine in the active position as shown).An engine spindle jig 790 and spindle slide structure 792 are componentsof engine swapping mechanism 762 a that facilitate rotational andvertical movement of the upper rocket engine 766 a and upper jet engine764 a. A variable pitch mechanism 794 is coupled to upper rocket engine766 a to facilitate angling of upper rocket engine 766 a when in theactive position (shown in FIG. 7G). A rocket nozzle extension 796 isprovided to extend the rocket nozzle as desired when in the activeposition (e.g. to expel hot exhaust gasses away from the fuselage of theaircraft to avoid heat-related damage).

FIG. 7D shows planetary module 760 with upper jet engine 764 a moved upto an active position and lower jet engine 764 b moved down to an activeposition. In the active positions, upper jet engine 764 a and lower jetengine 764 b align with air intake openings and exhaust openings so thatthey can operate in air. Upper rocket engine 766 a and lower rocketengine 766 b remain in their inactive positions within planetary module770.

FIG. 7E shows planetary module 760 with both jet engines 764 a-b androcket engines 766 a-b in inactive positions. The locations are swappedcompared with FIG. 7C, with upper rocket engine 766 a in the upperinactive position closer to the active position and lower rocket engine766 b closer to the active position.

FIG. 7F shows planetary module 760 with upper rocket engine 766 a andlower rocket engine 766 b in active positions where their exhaustnozzles direct exhaust gas out of planetary module 760 to propel theaircraft.

FIG. 7G shows an alternative arrangement for rocket engines 766 a-b(which do not require an air intake) in planetary module 760. In thisview rocket engines 766 a-b tilt outwards so that their exhaust gassesare directed out of planetary module 760 while nose sections remaininside planetary module 760. Opposed screw mechanisms for raising and/orlowering either the feed end or discharge ends of the rocks are providedso that the rocket engine can be inclined at a variety of angles,including parallel. Angling of rocket engines in this manner mayfacilitate stability of an aircraft, e.g. upper rocket engine 766 a andlower rocket engine 766 b may be controlled to maintain a stableorientation, for example during re-entry.

FIG. 8 shows another example of a planetary module 800 including two jetengines 802, 804. In this example, jet engines 802, 804 share an airintake manifold 806, which has two air intakes, an upper air intake 808and a lower air intake 810 (both of which are flush in thisarrangement). Shared air intake manifold 806 is configurable so that aircan be drawn from above, below, or both above and below. A gate valve812 is provided that can divide the air intake manifold 806 in two. Inthis situation, the upper jet engine 802 draws air from an upper intake808 and the lower jet engine 804 draws air from lower intake opening810. The upper jet engine 802 expels exhaust gasses outward throughupper exhaust opening 814 and the lower jet engine 804 expels exhaustgasses outward through lower exhaust opening 816. In some cases, bothupper jet engine 802 and lower jet engine 804 may draw air through thesame opening. A gate valve 818 is provided to close off lower air intake810 so that both upper jet engine 802 and lower jet engine 804 draw airthrough the shared air intake manifold 806 from the upper air intake808. For example, when an aircraft containing planetary module 800 ison, or close to the ground (e.g. during take-off and/or landing) gatevalve 818 may be closed in order to avoid sucking in debris from theground and to avoid creating a safety hazard if there are people nearby.This intake bypass method can be used in modules where the enginesinstead of being in the X configuration are both parallel with thecraft's upper and lower exterior surfaces.

FIG. 9A shows a side-view cross sectional view of a planetary module 900with an engine swapping mechanism 902 that is configured to swap a jetengine p-8 and a rocket engine p-9 between an active position and one ormore inactive positions. An axis of rotation p-36 extends parallel tothe jet engine p-8 and the rocket engine p-9 (i.e. perpendicular to thecross section shown) and allows engines to rotate using arms p-37 sothat one of the engines is aligned with the exhaust duct p-35 and may beconsidered in an active position. The active position may also alignwith an air intake so that a jet engine is aligned with both air intakeand exhaust outlets (while the rocket engine may not require an airintake, the active position may align the rocket engine similarly to thejet engine so that a rocket engine lies between air intake and exhaustopenings in the active position.) When in an inactive position, anengine is not aligned with an exhaust opening (or air intake opening)and is not functional. This position may be sufficiently removed fromthe active position to allow maintenance while the engine in the activeposition is in operation. For example, both jet engine p-8 and rocketengine p-9 are in inactive positions in FIG. 9A. A second engineswapping mechanism 904 is shown in the lower half of planetary module900. Engine swapping mechanism 904 may be a mirror image of engineswapping mechanism 902, and is configured to couple engines betweenintake and outlet openings on a lower surface of planetary module 900.

FIG. 9B shows a top view of planetary module 900 and engine swappingmechanism 902. Jet engine p-8 and rocket engine p-9 are mounted on armsp37 so that they are rotatable about central axis p36. Either one may beput in an active position where it is aligned with exhaust p-35.Flexible fuel lines p14 and p15 are provided to supply fuel to jetengine p-8 and rocket engine p-9 respectively. Air intake opening p12and exhaust opening p13 extend through an upper surface of planetarymodule 900 (it will be understood that FIG. 9B shows a cut-away view andthat a top surface generally extends over engine swapping mechanism 902leaving only openings p12 and p13 extending into the interior ofplanetary module 900). Using the same module and swapping and supportmechanism may save space and lessen weight.

FIG. 9C shows a vertical cross section of planetary module 900 with jetengines in active positions. For example, upper jet engine p-8 is in theactive position so that it can receive air from air intake opening p12and expel exhaust gas through exhaust opening p13. It can be seen thatplanetary module 900 is contoured to allow thrust to be generated in asubstantially horizontal direction. For example, air flows from airintake p12 through jet engine p-8 and out exhaust opening p-13 in astraight line (arrows indicate air flow through jet engines). An exhaustnozzle 910 is provided at exhaust opening p13 to direct exhaust gassesand provide further control of thrust.

FIG. 9D shows another cross section of planetary module 900 along aplane that is at 90 degrees to the plane of FIG. 9C. This view looksdirectly into intake opening p12 and shows a fin 950 that runs along thedirection of the jet from intake opening p12 to exhaust nozzle 910 andthat covers an engine in the active position (fin 950 may be consideredan engine cover-rudder because it combines the function of covering theengine and acting as a rudder). Fin 950 may be used instead of fins on afuselage (e.g. instead of fins 104 a-d of FIG. 1A). A similar fin 952extends along the underside of planetary module 900.

FIG. 9E shows an alternative embodiment with a low-profile planetarymodule 990 that also includes top and bottom fins 992, 994 respectively,which extend along upper and lower surfaces of planetary module 990.Fins 992, 994 cover engines and act as rudders and may be consideredengine cover-rudders. Fins 992, 994 may be used instead of fins on afuselage (e.g. instead of fins 104 a-d of FIG. 1A).

While various examples of aircraft with circular symmetry areillustrated here, it will be understood that planetary modules may beused in a range of aircraft that includes aircraft that may not becircularly symmetric. FIG. 10A shows an example of an aircraft 1000 thathas a circular central portion 1004 and has planetary modules 1002a-dmounted outside the central portion in an outer portion 1006 that isnot circularly symmetric. Aircraft 1000 may produce lift when it moveslaterally in any direction so that the advantages of rotatable planetarymodules are substantially as discussed above even though aircraft 1000is not substantially symmetric. For example, circular central portion1004 may have a profile that creates lift when it travels laterallythrough the air and/or outer portion 1006 may have a profile thatcreates lift when it travels laterally through the air.

FIG. 10B shows a view of aircraft 1000 without the outer surface ofaircraft 1000 to show the planetary modules 1002 a-d mounted with ringsof electromagnetic elements as parts of an electromagnetic suspensionsystem that allow planetary modules 1002 a-d to be rotated as needed.

FIG. 11 shows an example of an aircraft 1100 with circular symmetry thatis configured for carrying passengers. FIG. 11 includes cutaway sectionsthat show a passenger cabin 1102 that extends in a ring-shaped outerportion of aircraft 1100, with planetary modules and other aircraftsystems in an inner portion of the aircraft. In this ring configuration,the passenger cabin 1102 has views out of the aircraft that areunobstructed by wings or engines and the engines are all within arelatively compact portion of the aircraft so that fuel lines,electrical lines, and other conduits are short, and thus infrastructuremay be efficiently provided. A ring configuration allows passengers toget up and walk around easily and facilitates delivery of food andbeverages to passengers. An automated delivery system may be provided todeliver items from a central location to passengers seated in such apassenger cabin.

FIG. 12 shows a passenger aircraft 1200 in cross section including thepassenger cabin 1202 extending around a central portion of the aircraftthat contains the planetary modules 1204 a-c, which are illustrated incutaway view to clearly show how planetary modules 1204 a-c are mounted.In some embodiments, a central portion and an outer ring containing apassenger cabin may rotate relative to each other and may be coupled byan electromagnetic suspension system. FIG. 12 also shows a gyroscopicsystem 1206, in this example, extending around passenger cabin 1202 toprovide stability. For example, a spinning magnetic ring may be spun athigh speed in gyroscopic system 1206 to stabilize aircraft 1200.

FIG. 13 shows a cutaway view of a circularly symmetric aircraft 1300that includes planetary modules 1302 a-d and a central maintenance area1304. Central maintenance area 1304 provides access to planetary modules1302 a-d through corresponding airlocks formed by pairs of doors. Forexample, planetary module 1302 a is connected to central maintenancearea 1304 through an airlock 1306 that is formed by doors 1308 a-b. Acentral elevator 1310 is provided to access different levels withincentral maintenance area 1304 and may lead to a bridge deck located atthe highest level of central elevator 1310. Central maintenance area1304 may be maintained at atmospheric pressure so that crew can workthere even when aircraft 1300 is at high altitude, or is in space. Otherportions of aircraft 1300 may not be at atmospheric pressure. In somecases, planetary modules may be pressurized during operation. In othercases, planetary modules are not pressurized during operation but may bepressurized to allow maintenance. Airlocks may allow crew members toaccess planetary modules regardless of conditions (e.g. crew members mayput on space suits and enter planetary modules that are not pressurizedvia airlocks). Passenger cabins 1320 are located in areas of aircraft1300 between planetary modules as shown and are isolated from planetarymodules 1302 a-d. Planetary modules 13002 a-d are located in secure,insulated, and pressurized rooms 1322 a-d respectively. Rooms 1322 a-dmay provide security by preventing passenger access to planetary modules1302 a-d and may enhance safety of passenger cabins 1320 by reducingrisk of injury in case of fire or mechanical failure in a planetarymodule. Pressurized corridor cabins 1324 extend around cabins 1320 androoms 1322 a-d to allow passengers and crew to move around betweencabins 1320.

FIG. 14 illustrates an example of an aircraft 1400 that includesplanetary modules 1402 a-g as in previous examples (e.g. containing jetengines and/or rocket engines). In addition, aircraft 1400 includesbooster rockets 1406 a-d to provide additional thrust to get off theground and get into space, or near space. Booster rockets 1406 a-d maybe solid-fuel rockets or other one-time use rockets. Alternatively,booster rockets 1406 a-d may be reusable. Booster rockets are detachablefrom aircraft 1400 so that they may be detached when they are depleted.Attachments 1408 a-b may be latches that can unlatch to allow boosterrockets 1406 a-b respectively to fall away from aircraft 1400 (boosterrockets 1406 c-d are only partially visible in FIG. 14 so thatcorresponding attachments are not visible).

FIG. 15 shows an example of an aircraft 1500 that includes threeplanetary modules 1502 a-c instead of four, or eight planetary modulesas shown in prior examples. It will be understood that the number ofplanetary modules is not limited to any particular example shown hereand that aspects of the present technology may be implemented with anysuitable number of planetary modules. Other aspects shown in drawingshere are also non-limiting and are provided for illustration.

FIG. 16 shows an example of an aircraft 1600 that includes fourplanetary modules in a fuselage that is not circular in cross sectionalong a horizontal plane and includes a cutaway portion 1602 showing howa jet engine is mounted horizontally without redirection of intake oroutput.

In some cases, it may be preferable for an aircraft to have a crosssectional shape that is not symmetric, e.g. that has a leading edge witha different shape to its trailing edge. A non-symmetric shape may beachieved in various ways. Lift may be modified by appropriatelymodifying the cross-sectional profile of an airfoil. In the case of anaircraft that does not have separate wings, the shape of the body of theaircraft may be modified by adding one or more components that arenon-symmetric, while one or more central portions (e.g. aircraftfuselage) are symmetric (e.g. circularly symmetric so that there is nofixed “leading edge” or “trailing edge”).

FIG. 17 shows an example of an aircraft 1700 with a lift profileassembly, or LPA 1702, which is shown in a pull up portion of thedrawing for illustration of features that would be hidden from view whenLPA 1702 is coupled to fuselage 1704. LPA 1702 forms an outer ring ofaircraft 1700, which modifies the profile of aircraft 1700 so that it isnot symmetric and has a blunt rounded leading section with the trailingsection being more pointed (this may be similar to an aircraft wing orother airfoil shape). In this example, LPA 1702 modifies thecross-sectional shape of aircraft 1700 (e.g. as compared with crosssectional shape of aircraft 100 shown in FIG. 1B) so that lift isincreased. It will be understood that cross sectional shape may bemodified in various ways and such changes are not limited to increasinglift.

Fuselage 1704 has an upper rim 1706 on its upper surface and a similarlower rim on the lower surface (only the upper surface is visible inFIG. 17). Upper rim 1706 and corresponding lower rim (not shown) arerecessed ring-shaped assemblies that are configured to accommodatecorresponding ring-shaped rims 1708, 1710, that are located along theinner surface of LPA 1702. Thus, upper rim 1706 engages rim 1708 and thelower rim (not shown) engages rim 1710 to maintain LPA 1702 in placewith respect to fuselage 1704 while controlling rotation of LPA 1702about fuselage 1704. Rims 1708, 1710 mirror corresponding rims and allowfor some rotational clearance between components. Additional views ofexamples of this engagement are shown below.

An LPA such as LPA 1702 may be coupled to a fuselage such as fuselage1704 in various ways including using techniques described above forcoupling planetary modules to a fuselage, e.g. electrodynamic suspensionusing time-varying magnetic fields to induce eddy currents that createrepulsive magnetic fields. The repulsive magnetic field holds the twoobjects apart or, at least, reduces contact. Time varying magneticfields can be caused by relative motion between two objects such asbetween an electrodynamic ring around a fuselage and a correspondingelectrodynamic ring in an LPA. Magnetic fields may be controlled tomaintain a fixed distance between an outer surface of a fuselage and aninner surface of the LPA. Electromagnetic components may lock intoposition and electrodynamic suspension may be switched off when they areexpected to maintain the same orientation for an extended period. Whenan LPA is to be rotated, the electrodynamic suspension may be activatedso that the LPA is rotated with respect to the fuselage. In some cases,stepper motors, servo motors, or other electrical motors are used tomechanically turn planetary modules within an aircraft. Rotationalsupport components (RSC) and Rotational Position Components (RPC) may beprovided along engaged rims that oppose each other to facilitaterotation of LPA 1702 about fuselage 1704. RSC may refer to systems thatinclude such components as bearings, housings, electromagnetic and/orelectrodynamic suspension, etc. RPC may refer to systems that use servo,fly-by-wire, electromagnetic position regulator, actuators, or othercomponents. Such systems may be combined and may be used to provideaccurate support and placement of LPA 1702 about fuselage 1704. Rims,such as rims 1706, 1708, 1710, may include one or more RSC and/or RPCcomponents.

A second pair of rims (not visible in FIG. 17) are provided along theinner surface of LPA 1702 to engage outer rims 1712 of fuselage 1704. Insome cases, more than two such pairs of rims may be provided. Anyopposing rims may be provided with RSC and/or RPC components to ensurestructural integrity of aircraft 1700 when subject to high loads, e.g.during maneuvers that subject aircraft 1700 to high g-forces and toallow rotational adjustment of LPA 1702 with respect to fuselage 1704 asdesired.

FIG. 18 shows another view of aircraft 1700, in this case, with LPA 1702and fuselage 1704 in operational position so that they are coupled toeach other, with some clearance between them to allow rotationalmovement. The interlocking features of the outer surface of fuselage1704 and inner surface of LPA 1702 ensure close alignment of thesecomponents so that the profile of aircraft 1700 remains the same, whilethe orientation may change. The interlocking features such as rims,recesses, bearings, RPC and RSC components, etc. are not visible in FIG.18.

The leading edge 1820 of LPA 1702 of aircraft 1700 presents a rounded,blunt exterior surface, while the trailing edge 1822 forms a tapered,pointed edge (examples of cross-sectional views are provided below).While fuselage 1704 may be circularly symmetric about a central axis sothat it has the same profile along any vertical plane through itscenter, LPA 1702 is non-symmetric as shown, having a leading edge andtrailing edge that enhance aerodynamic performance of aircraft 1700. Inparticular, a non-symmetric profile may provide greater lift than acorresponding symmetric profile would. By rotating LPA 1702 aboutfuselage 1704, the orientation of optimum lift may be changed accordingto the direction of travel. This may be achieved without rotatingfuselage 1704. As discussed above, changes in direction of travel may beachieved by changing orientation and/or power of one or more thrustgenerators (e.g. jet engines) mounted in planetary modules and/or use ofrudders, fins, or other elements to affect airflow.

Orientation of LPA 1704 with respect to fuselage 1702 may be active(e.g. using servo motors, or other RPC components to rotate LPA 1704about fuselage 1702) or may be passive (e.g. using forces generated bychanges in orientation to rotate LPA 1704 about fuselage 1702) or mayuse a combination of active and passive techniques. For example, thecenter of mass of LPA 1704 may be towards trailing edge 1822 so thatwhen aircraft 1700 turns to the right, centrifugal forces tend to turntrailing edge 1822 outwards from the turn direction and this reorientsLPA 1704 with trailing edge 1822 away from the direction of travel andleading edge 1820 facing the direction of travel. Regulation of rotationof LPA 1704 may be achieved using RPC and RSC components, for example,applying dampening and breaking forces to avoid sudden changes inorientation of LPA 1704.

FIG. 19 shows aircraft 1700 in cross-section along a vertical plane thatintersects the central axis of fuselage 1704. The interlocking featuressuch as rims, recesses, bearings, RPC and RSC components, etc. areomitted from FIG. 19 for simplicity of illustration. It can be seen thatLPA 1702 represents a significant volume near trailing edge 1822, whileit represents a small volume along leading edge 1820. Thus, centrifugaland aerodynamic forces tend to turn LPA so that leading edge 1820rotates in the direction of a turn and trailing edge 1822 rotates awayfrom the direction of the turn so that leading edge 1820 continues tolead during and after a turn. One or more fins, rudders, or otheraerodynamic components may be provided to enhance this tendency and toprovide additional stability. An LPA such as LPA 1702 may be assembledfrom two or more components and may be built around a fuselage, such asfuselage 1704 so that a fuselage and LPA may be inseparable without somedisassembly of one or both components.

FIG. 20 illustrates the aerodynamic shape of an aircraft 2000 thatprovides an example of how such an aircraft may be formed to have anairfoil cross section along different vertical planes extending parallelto the direction of travel. FIG. 20 shows a cross section along a planethat bisects aircraft 2000. This illustrates the blunt leading 2020 edgethat extends around the front of aircraft 2000 and the more pointedtrailing edge 2022 that extends around the rear of aircraft 2000. FIG.20 shows LPA 2002 separately to illustrate its shape and some of theattachment features of LPA 2002. Rims 2008, 2010, 2012 (which may haveRSC and/or RPC components) are shown engaged with correspondingconnecting components 2038, 2040, 2042 of LPA 2002. Connectingcomponents 2038, 2040, 2042 may include support blocks having matchingconvex surfaces corresponding to rims 2008, 2010, 2012 and may becapable of locking in a fixed manner, or in a rotationally free manner,and may, in some configurations allow detachment of LPA 2002 fromaircraft 2000 so that LPA may be released and separated. For example,since an LPA is only needed for lift when flying in air and is notneeded in space, an LPA may be jettisoned when moving from atmosphere tospace. In some examples, an LPA may include some fuel storage capacitythat is used during takeoff and is partially or completely empty when anaircraft reaches space. Such an LPA may be jettisoned as an empty fueltank and may be recovered (e.g. from the sea) for subsequent use.

According to aspects of the present technology, an aircraft/spacecraftmay take advantage of favorable properties of certain shapes for use inan aircraft fuselage. For example, a fuselage may include a portion thathas an oblate spheroid shape (also referred to as an “elliptical sphere”or squashed sphere). A structure having an oblate spheroid shape may bestrong for its weight (i.e. high strength to weight ratio). Because sucha shape has radial symmetry, it may be formed of prefabricated portions(e.g. wedge-shaped portions) that can be combined together by methodsknow in the art to form a unified structure. This may allow easytransportation (e.g. transported by other aircraft/spacecraft).

FIG. 21A shows an example of an aircraft fuselage 2150 showing oblatespheroid portion 2152 and an LPA (lift profile assembly) portion 2154(shaded). Oblate spheroid portion 2152 is symmetric about a central axis2156. FIG. 21A is a cross-sectional view along a horizontal planeperpendicular to central axis 2156.

FIG. 21B shows aircraft fuselage 2150 in cross-section along a verticalplane that includes central axis 2156. It can be seen that LPA portion2154 extends laterally from the right of oblate sphere portion 2154along horizontal plane 2154 (horizontal plane of FIG. 21A), which isperpendicular to central axis 2156. The combination of oblate spheroidportion 2152 and LPA 2154 form an airfoil shape (e.g. when aircraft 2150travels in air from right to left in the views shown). The oblatespheroid portion 2152 may have a high strength to weight ratio and may(in combination with LPA portion 2154) generate significant lift so thatit provides multiple advantages in an aircraft fuselage. Note that whileFIG. 21B shows a cross-section through the middle of aircraft fuselage2150 (through central axis 2156), the combination of oblate spheroidportion 2152 and LPA portion 2154 provides a similar cross-section atother locations across aircraft fuselage 2150 so that aircraft fuselage2150 generates lift at all or substantially all locations laterallydisplaced from central axis 2156.

As in some previous examples, an LPA may be rotatable during flight(e.g. rotatable about central axis 2156). In other examples, an LPA maynot be rotatable. In some cases, an LPA and an oblate spheroid may beformed as an integrated unit (e.g. with a common frame and outer layer),which may provide smooth outer surfaces with low drag.

FIG. 21C shows a perspective view illustrating the shape of aircraftfuselage 2150 and illustrating the locations of frame members 2158 a-b.Frame member 2158 a runs from nose to tail while frame member 2158 bruns laterally. Frame members 2158 a-b intersect at central axis 2156.Additional frame members may be provided (e.g. radiating out from acentral axis and/or running nose to tail and/or laterally), often ascross braced ribs and spars.

While an aircraft fuselage may be based on an lift enhanced oblatespheroid shape (e.g. LEOS shape), additional portions may extend beyondthe oblate spheroid portion, such as an LPA. In some cases, wings and/ora tail portion may also extend from an oblate spheroid portion creatingan asymmetric perimeter profile (APP.) FIG. 21D shows an example of anaircraft 2171 that includes an oblate spheroid portion 2173, wings 2175,2177, and a tail 2179 extending from oblate spheroid portion 2173. Inthis example, jet engines 2181 a-c are mounted on the underside ofaircraft 2171.

FIGS. 21E-F illustrate an additional example of an aircraft fuselage2185 that is based on an oblate spheroid shape and the advantagesprovided by such a shape. Instead of a single oblate spheroid, aircraftfuselage 2185 includes three oblate spheroids 2187-2189 joined togetherin such a way that each generates lift. Each oblate spheroid 2187-2189may be formed as previously described so that it has an airfoil shape incross section along a plane running nose-to-tail at any lateral location(e.g. similar to the cross-sectional profile of FIG. 21B). Centraloblate spheroid 2187 is larger than right oblate spheroid 2188 and leftoblate spheroid 2189.

An aircraft based on fuselage 2185 may be powered in any suitablemanner. For example, FIG. 21F shows right jet engine 2191 and left jetengine 2182 that provide thrust on either side to propel aircraftfuselage 2185 forward.

FIG. 21G shows another example of an aircraft fuselage 2193 that istriangular in shape along a horizontal plane (FIG. 21G shows aperspective view). Three modules 2195-2197 each include an upper jetengine and a lower jet engine (not visible) to provide thrust along ahorizontal plane. Modules 2195-2197 may be rotatable or may be fixed inposition. Aircraft fuselage 2193 may generate lift across its entirelateral extent by having a lift-producing cross-sectional shapethroughout (e.g. a cross-sectional shape similar to the example of FIG.21B).

Thrust to drive an aircraft with an oblate spheroid structure may begenerated by multiple modules (e.g. planetary modules with one or morejet and/or rocket). In some cases, such modules may be rotatable withrespect to a fuselage. In some cases, modules or engine housings mayhave a fixed orientation with respect to the fuselage.

FIGS. 22A-B show an example of aircraft fuselage 2150 that includes aplurality of modules 2260 a-d that generate thrust. Each module includesan upper jet engine directed above the upper surface of aircraftfuselage 2150 and an opposed lower jet engine directed below the lowersurface of aircraft fuselage 2150 (only upper jet engines may be seen inthe top-down view of FIG. 22A). For example, module 2260 b includesupper jet engine 2262 b directed above upper surface 2264 of aircraftfuselage 2150 and lower jet engine 2266 b directed below lower surface2268 of aircraft fuselage 2150. Module 2260 c includes upper jet engine2262 c directed above upper surface 2264 of aircraft fuselage 2150 andlower jet engine 2266 c directed below lower surface 2268 of aircraftfuselage 2150. Module 2260 d includes upper jet engine 2262 d directedabove upper surface 2264 of aircraft fuselage 2150 and lower jet engine2266 d directed below lower surface 2268 of aircraft fuselage 2150.Module 2260 a includes upper jet engine 2262 a directed above uppersurface 2264 of aircraft fuselage 2150 and a lower jet engine (notvisible in FIGS. 22A-B) directed below lower surface 2268 of aircraftfuselage 2150. In general, upper jet engines 2266 a-d and lower jetengines 2266 a-d generate thrust to propel the aircraft through the air(or, with jets replaced by rockets, may propel the aircraft throughspace). The upper jet engines and lower jet engines of the plurality ofmodules may be controlled (e.g. by a central controller) to controlthrust generated by each individual jet engine, which collectivelygenerate a combined thrust in a particular direction (combined thrustvector). Orientation of the aircraft may be controlled by controllingsuch a thrust vector. For example, in order to turn about central axis2154 (i.e. to control yaw), the thrust vector may be changed byincreasing thrust generated by jet engines of module 2260 a comparedwith thrust generated by jet engines of module 2260 c or by increasingthrust generated by jet engines of module 2260 c compared with thrustgenerated by jet engines of module 2260 a. In order to point upwards ordownwards (control pitch) thrust of lower jet engines 2266 a-d may beincreased or decreased compared with thrust of upper jet engines 2260a-d. Upper jet engines 2260 a-d and lower jet engines 2266 a-d are fixedwith respect to fuselage 2150 in this example (e.g. oriented alongcorresponding planes that are parallel to the plane of aircraft fuselage2150) and the central controller is configured to change direction andmagnitude of the combined thrust vector by changing magnitudes of thrustgenerated by individual ones of the upper jet engines 2262 a-d and lowerjet engines 2266 a-d (i.e. there is no change in the direction of thrustof any individual jet engine where engines are fixed in position).

FIG. 22C shows an example of a central controller 2270 configured toprovide control signals to upper jet engines 2262 a-d and lower jetengines 2266 a-d of modules 2260 a-d respectively. Each control signalmay provide individual control the respective jet engine (e.g. tocontrol thrust of each jet engine individually). Upper and lower jetengines may be rotatable or may have fixed orientations (e.g. may bepermanently mounted with a particular orientation). Upper and lower jetengines may be oriented in parallel or may be oriented differently (e.g.at different angles relative to horizontal plane 2154 and/or withrespect to a center line). Combined thrust of the upper and lower jetengines may be controlled in both magnitude and direction by controllingthrust generated by individual ones of the upper jet engines and thelower jet engines.

While an LPA may be formed as an integral component of an aircraftfuselage in some examples, in other examples, an LPA may be at leastpartially separable from another portion of an aircraft fuselage (e.g.from an oblate spheroid portion). This may allow an aircraft fuselage tohave two or more physical configurations.

FIGS. 23A-B illustrate an example of aircraft fuselage 2150 with LPA2154 configurable so that it allows multiple configurations of aircraftfuselage 2150. For example, FIG. 23A shows aircraft fuselage 2150 in afirst configuration, with LPA portion 2154 flush with oblate spheroidportion 2152 to provide an aerodynamic high-lift profile as previouslyshown (jet engines and other components are omitted for simplicity inthis view).

FIG. 23B shows aircraft fuselage 2150 with LPA 2154 in an extendedconfiguration in which it is displaced a distance d from oblate spheroidportion 2152 along horizontal plane 2154. The separation (a distance d)means that the concave inner surface of LPA 2154 is exposed and createssignificant drag as aircraft fuselage 2150 moves (e.g. moving from rightto left in this view). This drag may be used to slow down aircraftfuselage 2150 when reentering the earth's atmosphere from space,descending at a steep angle, or otherwise. In order to change from theflush lift-generating configuration of FIG. 23A to the extendedhigh-drag configuration of FIG. 23B. LPA 2154 may be mounted on asliding mechanism, on struts, or otherwise attached to oblate spheroidportion 2152 in a movable arrangement. Movement of LPA 2154 may beachieved using one or more actuators (e.g. one or more electric,hydraulic, pneumatic or other actuators).

FIGS. 23C-D show another example of aircraft 2000 (previously shown inFIG. 20) that includes LPA 2002, which is separable from the rest ofaircraft 2000. FIG. 23C shows aircraft 2000 in a high lift configurationwith low drag (streamlined configuration for flight). FIG. 23D showsaircraft 2000 in a high-drag configuration with LPA 2002 separated fromthe rest of aircraft 2002 as shown by arrows. FIG. 23E shows an exampleof aircraft 2000 including locations of mini-thrusters 2323 a-c arrangedalong a lower surface to generate thrust in a downward direction. Duringre-entry from space (in a shockwave re-entry position), aircraft 2000may be oriented so that instead of travelling nose-first, its lowersurface leads and it presents a large profile thus causing drag to slowits descent. Mini-thrusters 2323 a-c may provide thrust to further slowdescent in this position. Mini-thrusters 2323 a-c may be controlled by acentral controller such as central controller 2270 to achieve andmaintain a desired orientation (e.g. transverse to the direction oftravel for maximum drag). Subsequently, (e.g. at a lower altitude wherethere is more air and therefore more friction), mini-thrusters 2323 a-cmay be turned off, the orientation of aircraft 2000 may be modified to anose-first orientation and LPA 2002 may be moved to the high-dragconfiguration of FIG. 23D.

Advantages of an aircraft with a central axis such as central axis 2156is that it can have a high strength to weight ratio and it can beassembled from prefabricated portions.

FIGS. 24A-B show examples of how aircraft fuselage 2150 may be formedusing frame members 2460 a-h (rib-like frame members) that extend outfrom central axis 2154 (e.g. as previously shown in FIG. 21C). Framemembers may be formed of metal or other high-strength material and maybe joined together at central axis 2156. An outer layer of fuselage 2150may overlie frame members 2460 a-h. In FIG. 24A, frame members 2460 a-hare limited to oblate spheroid portion 2152 and do not extend into LPA2154, which may be a separate component that can be separated and/orrotated. Frame members 2460 a-h may be identical in this example (e.g.because oblate spheroid portion 2152 is symmetric about central axis2156), which may facilitate large scale production.

FIG. 24B shows an example in which frame members 2460 a-j extend throughthe entire fuselage 2150 (e.g. where LPA portion 2154 is integrated withoblate spheroid portion 2152). Frame members 2460 a-j are not identicalin this example as some frame members (e.g. frame members 2460 c-e) arelonger than others (e.g. frame members 2406 h-j).

In some examples, an aircraft fuselage may be assembled fromprefabricated portions that are bolted, welded, or otherwise attachedtogether when needed. An aircraft fuselage with a radial configuration(e.g. as shown in FIGS. 24A-B with frame members 2460 extending out fromcentral axis 2154) may be assembled from wedge-shaped portions that maybe compact enough to transport easily.

FIG. 24C shows an example of fuselage 2150 during assembly with portions2464 a-i in place (meeting at central axis 2156) and with portion 2464being moved into place to be coupled with neighboring portion 2464 i andportion 2464 a.

A central axis and/or modular construction may be applied to any of theaircraft described here including aircraft fuselage 2185. FIG. 24D showseach oblate spheroid 2187-2189 having a central axis, which may be alocation where wedge-shaped modules meet. For example, central oblatespheroid 2187 includes central axis 2470 and shows an example of awedge-shaped portion 2472 that may be prefabricated and separatelytransported prior to incorporation into aircraft fuselage 2185.

In some cases, it may be advantageous to couple an aircraft with one ormore other aircraft and/or spacecraft. For example, an aircraft may beprovided with an air-tight door and suitable coupling hardware to allowit to be coupled with corresponding hardware of another aircraft orother structure (e.g. space station).

FIGS. 25A-B illustrate an example of aircraft fuselage 2150 configuredwith air-tight doors and air-lock flanges for coupling withcorresponding air-lock flanges of other aircraft or other structures.

FIG. 25A shows a top-down view of aircraft fuselage 2150 including upperair-lock flange 2570, which extends about upper air-tight door 2172.Upper air-lock flange 2570 and air-tight door 2172 are circular and maybe aligned with central axis 2154 of oblate spheroid portion 2152. Inother examples, these features may be square, rectangular, or have anyother shape.

FIG. 25B shows lower air-lock flange 2574, which may be substantiallysimilar to upper air-lock flange 2570 and may extend around a lowerair-tight door (not visible in this view) which may be substantiallysimilar to upper air-tight door 2172, with a downward facing orientationinstead of the upward facing orientation of upper air-lock flange 2570and upper air-tight door 2172.

FIG. 25C shows a cross-sectional view of three aircraft 2580, 2582, 2584coupled together using air-lock flanges and with their air-tight doorsopen to create a shared volume 2586 that extends through the threeaircraft and may allow free movement of personnel and material betweenaircraft when docked in space. For example, a lower air-lock flange ofaircraft 2580 is coupled to upper air-lock flange of aircraft 2582.Lower air-tight door of aircraft 2580 and upper air-tight door ofaircraft 2582 are open. An upper air-lock flange of aircraft 2584 iscoupled to lower air-lock flange of aircraft 2582. Upper air-tight doorof aircraft 2584 and lower air-tight door of aircraft 2582 are open.This connects the interior spaces of the three aircraft to form a singlelarge space and allow rapid transfer of personnel and material.

FIG. 26 illustrates another example of three aircraft 2690, 2692, 2694,each equipped with upper and lower air-tight doors and upper and lowerair-lock flanges to allow coupling in space. Aircraft 2690, 2692, 2694are aligned so that the air-lock flanges align and an air-lock flangemay seal against corresponding air-lock flange of an opposing aircraftto allow docking. Once sealed, air-tight doors may be opened and theinterior spaces connected. While aircraft 2690, 2692, 2694 each haveboth upper and lower air-tight doors and corresponding air-lock flanges,in other examples, an aircraft may have only one such air-tight door andcorresponding air-lock flange (e.g. only on a top surface or only on abottom surface).

For purposes of this document, it should be noted that the dimensions ofthe various features depicted in the FIGS. may not necessarily be drawnto scale.

For purposes of this document, reference in the specification to “anembodiment,” “one embodiment,” “some embodiments,” or “anotherembodiment” may be used to describe different embodiments or the sameembodiment.

For purposes of this document, a connection may be a direct connectionor an indirect connection (e.g., via one or more other parts). In somecases, when an element is referred to as being connected or coupled toanother element, the element may be directly connected to the otherelement or indirectly connected to the other element via interveningelements. When an element is referred to as being directly connected toanother element, then there are no intervening elements between theelement and the other element. Two devices are “in communication” ifthey are directly or indirectly connected so that they can communicateelectronic signals between them.

For purposes of this document, the term “based on” may be read as “basedat least in part on.”

For purposes of this document, without additional context, use ofnumerical terms such as a “first” object, a “second” object, and a“third” object may not imply an ordering of objects, but may instead beused for identification purposes to identify different objects.

For purposes of this document, the term “set” of objects may refer to a“set” of one or more of the objects.

The foregoing detailed description has been presented for purposes ofillustration and description. It is not intended to be exhaustive or tolimit the subject matter claimed herein to the precise form(s)disclosed. Many modifications and variations are possible in light ofthe above teachings. The described embodiments were chosen in order tobest explain the principles of the disclosed technology and itspractical application to thereby enable others skilled in the art tobest utilize the technology in various embodiments and with variousmodifications as are suited to the particular use contemplated. It isintended that the scope of be defined by the claims appended hereto.

What is claimed is:
 1. An aircraft comprising: a fuselage that includes;an oblate spheroid portion that is symmetric about a central axis; and alift profile assembly extending laterally from a section of the oblatespheroid portion along a plane that is perpendicular to the centralaxis, the combination of the oblate spheroid portion and the liftprofile assembly having a combined upper surface and a combined lowersurface that define an asymmetric airfoil shape in cross-section along avertical plane such that horizontal movement of the fuselage through airproduces a lift force in a vertical direction; and a plurality ofmodules attached to the fuselage, each module including an upper enginehaving an outlet above the combined upper surface and an opposed lowerengine having an outlet below the combined lower surface.
 2. Theaircraft of claim 1 wherein the fuselage is circularly symmetric about acentral axis.
 3. The aircraft of claim 1 wherein each module isseparately rotatable about a vertical axis that extends parallel to thecentral axis to generate thrust on upper or lower planes parallel theaircraft's trajectory.
 4. The aircraft of claim 1 further comprising twoor more wings extending from the fuselage.
 5. The aircraft of claim 1wherein the lift profile assembly is rotatable about the central axis.6. The aircraft of claim 1 wherein the lift profile assembly is at leastpartially separable from the oblate spheroid portion by lateralseparation of the lift profile assembly and the oblate spheroid portionto reconfigure the aircraft from a lift-generating configuration to ahigh-drag configuration.
 7. The aircraft of claim 1 wherein the fuselageincludes a frame formed by frame members extending radially from thecentral axis.
 8. The aircraft of claim 1 wherein the fuselage is formedof prefabricated wedge-shaped sections that are joined along the centralaxis.
 9. The aircraft of claim 1 wherein upper engines and lower jetengines of the plurality of modules are configured to generate acombined thrust vector and a central controller is configured to controlthrust generated by individual ones of the upper engines and lowerengines to change the combined thrust vector and thereby changeorientation of the aircraft.
 10. The aircraft of claim 9 wherein theupper engines and lower engines are fixed with respect to the fuselageand the central controller is configured to change direction andmagnitude of the combined thrust vector by changing magnitudes of thrustgenerated by individual ones of the upper engines and lower engines. 11.The aircraft of claim 1 further comprising at least on air-tight doorand an air-lock flange extending about the air-tight door in a surfaceof the fuselage.
 12. An aircraft comprising: a fuselage having an ovalshape in cross-section along a horizontal plane and having an airfoilshape in cross-section along a vertical plane perpendicular to a primaryaxis of the oval shape, wherein the fuselage includes an oblate spheroidportion that is symmetric about a central axis and further includes alift profile assembly extending laterally from a section of the oblatespheroid portion along the horizontal plane; and a plurality of pairs ofengines, each pair of engines including an upper engine mounted above anupper surface of the aircraft and a lower engine mounted below a lowersurface of the aircraft, the upper engine and the lower enginecontrolled by a central controller.
 13. The aircraft of claim 12 whereinthe lift profile assembly is rotatable about the central axis.
 14. Theaircraft of claim 12 wherein the lift profile assembly is at leastpartially separable from the oblate spheroid portion from alift-generating configuration to a high-drag configuration.
 15. Theaircraft of claim 12 wherein the fuselage includes a frame formed byframe members extending radially from the central axis.
 16. The aircraftof claim 12 wherein upper engines and lower engines of the plurality ofmodules are configured to generate a combined thrust vector and acentral controller is configured to control thrust generated byindividual ones of the upper engines and lower engines to change thecombined thrust vector to thereby change a flightpath of the aircraft.17. The aircraft of claim 1 wherein each upper engine has an intakeabove the upper surface of the fuselage and each lower engine has anintake below the lower surface of the fuselage.
 18. The aircraft ofclaim 1 wherein each upper engine has an intake below lower surface ofthe fuselage and each lower engine has an intake above the upper surfaceof the fuselage.
 19. The aircraft of claim 1 wherein the lift profileassembly extends from a trailing section of the oblate spheroid portionto from a pointed trailing edge of the fuselage.
 20. The aircraft ofclaim 19 wherein the lift profile assembly extends around the oblatespheroid portion and forms a rounded leading section of the fuselage.